Avengers: Infinity War brings together a vast cast of Marvel stars. George Clooney. Tom Selleck. David Bowie's wife.

OK, so Clooney never played Nick Fury, Selleck was never Doctor Strange and Angie Bowie didn't get any further than a photo in a Black Widow costume. But they nearly did. Long before the success of the Marvel Cinematic Universe, there were many proposed Marvel movie ideas that never made it to screens.

Marvel's first movie was Captain America all the way back in 1944. Later, Marvel figurehead Stan Lee left behind the comics he had made his name writing and became the company's full-time Hollywood ambassador, shopping the comic characters to TV and movie producers.

The delightful Marvel Comics: The Untold Story by Sean Howe details how in the 1970s, '80s and '90s stars from Brigitte Nielsen and Carl Weathers to Leonardo DiCaprio came close to donning the capes and tights of Marvel's heroes.

Click through our gallery to see what those movies could have looked like, and try and tell us they wouldn't all have been amazing:

So why did none of these potential movies make it?

Sometimes the filmmakers simply didn't understand what they had. Production company Cannon films at one point worked on a draft of a script about Spider-Man in which our friendly neighbourhood wall-crawler literally turned into a tarantula.

Then there are the legal issues. The history of Marvel is a tangle of legal rights for films, toys and other spin-offs being farmed out to other companies -- frequently followed by decades spent trying to claw them back.

The rights to Spider-Man were a tangled web for decades until Spidey finally became part of the Marvel Cinematic Universe in time for Civil War and Spider: Man: Homecoming. Disney's deal with Fox could bring the X-Men into the fold, but aquatic antihero Namor the Sub-Mariner is still drowning in rights issues and conspicuous by his absence on the big screen.

Probably the most notorious -- and hilarious -- example of a tussle over rights is the 1994 "Fantastic Four" flick filmed by legendary B-movie producer Roger Corman. He threw the movie together on a shoestring so his rights wouldn't expire -- only for Marvel to take one look and throw money at the producers to bury the infamously shoddy affair:

Meanwhile some projects simply ran out of time. I'm a big fan of the Daredevil TV show on Netflix, but sadly, it put the kibosh on an intriguing 1970s-set proposal by Narc and Smokin' Aces director Joe Carnahan developed when Fox still held the rights to the horned hero. The project fizzled when the rights reverted to Marvel in 2012, but we can see what might have been in Carnahan's sizzle reel of atmospheric clips from classic '70s crime and blaxploitation movies:

And of course, many of these projects were conceived before 1989's "Batman" proved how much of a box office sensation a superhero could be. They were also in the works long before CGI helped special effects catch up with the characters' special powers.

But even now, with hero-packed team-ups like "Infinity War" and solo movies like "Black Panther" absolutely smashing the box office, there are still a number of other projects stuck in limbo.

We'll never know what 2015's Ant-Man would have looked like if original writer and director Edgar Wright had stuck around. Meanwhile toddler team-up Power Pack and martial arts mash-up Shang-Chi were previously announced by Marvel but are yet to go ahead. EVen more recently, an Inhumans movie was struck off the slate and turned into a TV show instead.

Still, there's plenty more where they came from, true believers. So let's salute the Marvel movies that never were, safe in the knowledge that there won't be a shortage of superhero showstoppers any time soon.

First published, May 11, 2006.
Update, May 4, 2018 at 10:10 a.m. PT: Adds references to the latest Marvel movie, Avengers: Infinity War.   

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